I just pulled out a test master for a record our band did in 1986, mastered by you at Masterdisk. The vinyl (or is it even vinyl?) is really heavy and stiff .... do you remember what material was used for those test masters? And can I get fewer plays out of it than the normal vinyl record? (I've always been reluctant to play it - I think it went into storage after 1 test listen way back when!)